I use Frontline Plus. I make sure to wait at least 5 days before giving Buster a bath after applying it. It figure he is better off dirty for a little bit that biting and scratching at himself. My vet told me they usually bite, feed, and jump off. She said if you see them crawling around on your dog then it is an infestation. I would definitely treat her.
Here is also a link to holistic treatments for fleas.
http://www.thewholedog.org/artfleas.html